I’m searching for a calendar app (no google), which supports recurring (RRULE:) events with exception data (EXDATA:) but I didn’t find any in F-Droid.
I really tried all apps I’ve found under the searching words “calendar” and “Kalender”, but none of them can import such events.
Does anyone know such an app?
Thanks in advance for suggestions
I use Simple Calendar but so far I know it support just the most default calendar format (ICS). May you have a chance to export it as ICS.
I have looked for a converter on github but without a success. In my understanding EXDATA is a Database format thats why it is not possible to convert to a ICS format.
You might look at Etar, default in LineageOS I think.
@Dalli75
Maybe was my question not precise enough …
Simply said, ICS calendar files are made of many text lines; each line defines one characteristic of event. Lines beginning with EXDATA define exception dates in a recurring events.
EXDATA is part of ICS specifications, but it was - as other ones too - implemented in a second time in a “extended” specification. That’s the reason, why it is not supported by all the ics calendars.
Anyway thanks a lot for your interest!
I was a little worried about having no answer … 
Yes, I do too, but in a common android phone.
It does not support EXDATA - neither through import files nor if you want manually add an exception in a recurring event.
And I think, there are no differences between the Etar on common android phones an the other one in LineageOS.
Have you considered asking the developers of one of those apps for this feature? I can’t find any feature requests on https://github.com/Etar-Group/Etar-Calendar/issues?q=is%3Aissue+exdata.
@TheLastProject
Thanks for the suggestion!
Until now I’ve only contacted the developer of Simple Calendar Pro. He said, he will give an eye on it, because he thinks, his app should have exceptions implemented.
But hey, it is a good idea, to make a request on github!
I’ll do it in one oft the next days.
I’ve just looked at the issue list of Etar on github.com and saw, there are already many open issues related to support exceptions in recurring events:
#891
#97
#15
The oldest one is from 9th August 2013, is still open and without a possible fix or workaround.
Actually, these issues concern with deleting a single instance of a recurring event, not direct with “support of EXDATA”. But they are strong related to my item, because I think, the app will not be able to import a recurring event with exceptions, so long as it cannot delete a single instance (= create an exception) in a recurring event.
If I’ve right understood all the issue reports read, the problem may be located in android system, that should allow exceptions only if the calendar app is synced with an online calendar (as google one), which supports exceptions. However it seems aCalendar (a google app) should support this feature.
That means for me:
As I don’t wont get a google account, I must a) build a “mycloud” webDAV server; b) install a webDAV software, that supports recurring events with exceptions; c) and synchronize it with the phone calendar app.
A project for the next coming lockdown 